Application value of modified rapid Carba NP test for the detection of carbapenemase-producing strains / 临床检验杂志

ABSTRACT

Objective To investigate the feasibility of modified rapid Carba NP test for the detection of carbapenemase,and analyze the differences between the modified method and Carba NP test.Methods A total of 264 strains of gram-negative bacillus,including 164 carbapenem-resistant strains and 100 sensitive strains,were collected,and their carbapenemase were detected by Carba NP test and the modified rapid Carba NP test,respectively.The differences between the two tests were evaluated based on PCR as a reference.Results Among 164 carbapenem-resistant strains,carbapenemase gene was detected in 144 strains by PCR.The carbapenemase gene was negative in 100 sensitive strains.Among 164 carbapenem-resistant strains,135 were positive for the Carba NP test,while 130 for the modified rapid Carba NP test.One hundred of sensitive strains were negative for the two Carba NP tests.Compared with the results of PCR,the sensitivity,specificity and Kappa value of the Carba NP test were 91.7％ (132/144),97.5％ (117/120) and 0.886,respectively,while those of the modified rapid Carba NP test were 89.6％ (129/144),99.2％ (119/120) and 0.879,respectively.There was no significant difference in the positive rates between Carba NP test and the modified rapid Carba NP test (x2 =1.45,P ＞ 0.05).Conclusion The modified rapid Carba NP test which has high consistency with the PCR method,is faster and cheaper than the Carba NP test,and may be applied to epidemiologic survey and the early monitoring of nosocomial infections.